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题库 / Prep2007E1-SC-23
While they remove carbon dioxide from the air, conserve soil and water, and house thousands of species, forests also supply potentially valuable pharmaceuticals, and, as sources of building material and firewood, that provide employment for millions worldwide.
pharmaceuticals, and, as sources of building material and firewood, that provide
pharmaceuticals, and sources of building material and firewood, are providers of
pharmaceuticals and, as sources of building material and firewood that are providing
pharmaceuticals and sources of building material and firewood, for providing
pharmaceuticals and, as sources of building material and firewood, provide
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错选D
【平行 修饰】
supply、provide两者平行，用and连接
此处的生词pharmaceuticals是药物的意思，和后面的building material完全是两种东西
sources是来源的意思，D中provide sources提供来源明显是错误的
！！需根据句意理解
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